Re: [PATCH v9 1/8] mm: Introduce memfd_restricted system call to create restricted user memory

Chao Peng
2022-10-28T06:17:23Z

On Wed, Oct 26, 2022 at 10:31:45AM -0700, Isaku Yamahata wrote:
> On Tue, Oct 25, 2022 at 11:13:37PM +0800,
> Chao Peng <chao.p.peng@linux.intel.com> wrote:
>
> > +int restrictedmem_get_page(struct file *file, pgoff_t offset,
> > + struct page **pagep, int *order)
> > +{
> > + struct restrictedmem_data *data = file->f_mapping->private_data;
> > + struct file *memfd = data->memfd;
> > + struct page *page;
> > + int ret;
> > +
> > + ret = shmem_getpage(file_inode(memfd), offset, &page, SGP_WRITE);
>
> shmem_getpage() was removed.
> https://lkml.kernel.org/r/20220902194653.1739778-34-willy@infradead.org

Thanks for pointing out. My current base(kvm/queue) has not included
this change yet so still use shmem_getpage().

Chao
>
> I needed the following fix to compile.
>
> thanks,
>
> diff --git a/mm/restrictedmem.c b/mm/restrictedmem.c
> index e5bf8907e0f8..4694dd5609d6 100644
> --- a/mm/restrictedmem.c
> +++ b/mm/restrictedmem.c
> @@ -231,13 +231,15 @@ int restrictedmem_get_page(struct file *file, pgoff_t offset,
> {
> struct restrictedmem_data *data = file->f_mapping->private_data;
> struct file *memfd = data->memfd;
> + struct folio *folio = NULL;
> struct page *page;
> int ret;
>
> - ret = shmem_getpage(file_inode(memfd), offset, &page, SGP_WRITE);
> + ret = shmem_get_folio(file_inode(memfd), offset, &folio, SGP_WRITE);
> if (ret)
> return ret;
>
> + page = folio_file_page(folio, offset);
> *pagep = page;
> if (order)
> *order = thp_order(compound_head(page));
> --
> Isaku Yamahata <isaku.yamahata@gmail.com>